Elongate barrier

ABSTRACT

An elongate barrier (1) including an elongate carrier (3) which is flexible in all directions along its length and capable of retaining in transverse section substantially a U-shape (15) having a base and opposite clamping members; and at least one resilient barrier member (17) extending along the length of the carrier and having a base portion (25) and a body portion (27), wherein the base portion of the barrier member is retained in the base of the carrier by the clamping members and the body portion projects from the carrier such that when the carrier is flexed, the barrier member is retained in the carrier.

FIELD OF THE INVENTION

The present invention relates to barriers and seals, in particularflexible barriers and a method for making flexible barriers. It will beconvenient to describe the invention with particular reference to brushtype barriers, however, it will be appreciated that the invention haswider application.

BACKGROUND AND PRIOR ART

Elongate brush barriers are well known and are utilised in a widevariety of commercial, domestic and industrial applications. Elongatebrushes are used extensively as draft seals around doorways and windows,light seals around doorways for dark rooms, automotive weather seals,and the like and may be used to seal out air, water, light, vermin,birds, sound, dust leaves, snow or the like. Elongate brushes are usedas spray supressants around wheel arches of heavy vehicles. They arealso used as sweeping or scrubbing brushes for road sweepers, carwashes, food processing apparatus, cleaning brushes for conveyors andthe like. They are used extensively as seals around aerobridges,scourers, spiral conveyors for fragile goods, electronic conductors,electromagnetic gasketting, just to name a few.

Conventional elongate brushes generally consist of a plurality ofbristles retained in a rigid U-shaped metal channel. The bristles aregenerally folded about a retaining wire and a rigid steel strip isroll-formed into a U-shaped channel which clamps the bristles about aretaining wire. Whilst such rigid elongate brushes are useful for manyapplications, the finished product is very rigid and generally linearand it is difficult, expensive, or not possible to form into a differentshape such as a circle, semi-circle, spiral or helix. Further the shapeof the backing or base of the U-shape is limited to either square orrectangular, according to the dimensions of the flat steel stock usedfor the backing. In many applications where hygiene or corrosionresistance is important, the backing must be galvanised or stainlesssteel, which adds to the cost of production. When complicated brushproducts such as spirals, circles or the like are required, the backingoften has to be welded or otherwise attached to a secondary carrier.

It would be desirable to provide for many applications an elongate brushwhich is flexible along its length so that the brush can be bent intoany desired configuration. For example, to a helix for rotating cylindersweepers, or conveyors, into a spiral for rotating disk sweepers, orsimply being able to be directed along a guide, for example in a channelaround door frames or the like where the brush is flexible enough to befed along the guide off a spool.

There have been a number of attempts to manufacture a flexible elongatebrush. One method involves the extrusion of a thermoplastic backingaround the base of a line or bristles with the bases of the bristlesbeing melded into the extruded backing using infra-red radiation or somesimilar heat source. Whilst the resultant elongate brush may be flexibleto some extent, it suffers from a number of disadvantages. First, it isnecessary for the extruded backing and bristles to be of a compatiblematerial such that the backing will meld to and about the bristles whenheated. This is acceptable when bristles made from propylene orpolyethylene are used. Natural or heat sensitive bristles such ashorse-hair or cotton will generally degrade at the temperaturesnecessary for co-extrusion with a backing. Moreover such fibres are notmeldable with thermoplastic backing materials. Unless the melding of thebristles and backing is secure, bristles may readily fall away from thebacking. Furthermore, it is necessary to keep the array of bristles inan orderly manner when the backing is applied. It may be necessary tokeep the bristles orderly by providing sewn or woven retaining threadsclose to the base of the bristles which are to be melded. One othermethod involves the steps of knitting bristles into an orderly array,heating the bases of the bristles to melt them together along a centralline, slitting the melted bristle bases to form two brushes, extruding abacking on each brush then cropping the bristle tips. Such a process,however, involves considerable work and hence adds to the cost ofmanufacturing such product without producing a superior product.

Whilst the problems associated with manufacture of flexible brushes havebeen discussed, similar problems exist in manufacture of flexibleelongate "fin" type barriers such as blade wipers, squeegees or flexibleblade-type seals. In such cases the problems associated with providing aflexible carrier exist, these problems being virtually identical tothose faced with flexible elongate brushes.

Accordingly, there is a need to provide an elongate barrier which isflexible and which overcomes one or more of the problems of the priorart.

SUMMARY OF THE INVENTION

In accordance with the present invention there is provided an elongatebarrier including an elongate carrier being flexible in all directionsalong its length and capable of retaining in transverse sectionsubstantially a U-shape having a base and opposite clamping members; and

at least one resilient barrier member along the length of said carrierand having a base portion and a body portion, wherein the base portionof said barrier member is retained in the base of said carrier by saidclamping members and said body portion projects from said carrier suchthat when the carrier is flexed said barrier member is retained in saidcarrier.

The barrier is generally elongate and may be of any suitable length. Thebarrier may act passively to prevent or inhibit passage of air, water,such as seals against dust, dirt, light, birds, vermin, leaves, snow orthe like. In another embodiment the barrier may be active in performinga sweeping or cleaning action such as a wiper or brush.

The barrier may act to selectively allow some things past such as air,but at the same time preventing another thing past such as water. Theuses of such barriers will be well known in the art.

The elongate barrier includes an elongate carrier. The carrier isflexible along its length in all directions i.e. up and down, side toside and also may be twisted along its length. In other words theelongate carrier generally has an axis running along the length of thebarrier and the carrier is flexible in two dimensions along said axisand may also be twisted about its axis. Across its width, i.e.perpendicular to the axis the carrier is capable of retaining intransverse section substantially a U-shape or variation thereof such asa C-shape, which has a base and opposite clamping members. Preferably,said carrier is deformable into a selected shape in transverse sectionand the carrier retains that selected shape after such deformation.Preferably, the selected shape is a U-shape or C-shape in transversesection. Preferably, the carrier consists of one or more flexiblelongitudinal members which run along the length of the carrier and oneor more transverse members which run across the width of the carrier,the transverse members being deformable into a desired shape andretaining that shape once so deformed. The longitudinal member ormembers are primarily to maintain the transverse members in an orderlymanner or to hold the transverse members in a spaced relationship to oneanother. The transverse members may consist of a plurality of wiresegments oriented across the width of the carrier. The carrier mayconsist of a substantially flat metal strip which has portions stampedor otherwise cut out so that the strip is flexible in all directionsalong its length and has a plurality of fingers projecting therefromwhich form the clamping members. Preferably the transverse memberconsists of a continuous length of wire bent or otherwise formed into asinuate shape which extends along the length of the carrier and zigzagsacross the width of said carrier. The wire is preferably a bright lowcarbon steel wire.

An essential feature of the carrier is its resistance to splay orcapability of retaining the desired U-shape. This feature may becontrolled by three factors being wire diameter, wire ultimate tensilestrength and frequency or number of zigzags or "picks" of wire over agiven length of carrier. A pick corresponds to one transverse member. Itis possible to achieve increased shape retention by increasing thetensile strength of the wire and/or diameter. Preferably the resistanceof the carrier to splay once in the desired U-shape is greater thanabout 50 Newtons, more preferably greater than about 100 Newtons.

Table A below gives a general indication of shape retention orresistance to splay when the variables above are tested:

                  TABLE A    ______________________________________    DIAMETER  TENSILE     PICKS PER  RESISTANCE    OF WIRE   STRENGTH    METER      TO SPLAY    (MILLIMETERS)              (HECTOBARS) (PPM)      (NEWTONS)    ______________________________________    0.75       85-100     394-413    120    0.67      147-170     275.5-295  112    0.67      147-170       315-334.5                                     119    0.67      147-170     354-374    130    ______________________________________

In this embodiment, the longitudinal member(s) consist of one or morestrands which may be interwoven, knitted or otherwise cooperating withthe transverse member to retain said wire in a sinuate shape and tomaintain a spaced relation between adjacent portions of the transversemember.

In one embodiment the longitudinal members and transverse members may befully or partially enveloped in a flexible substrate. The flexiblesubstrate may be any suitable plastic or textile material including butnot restricted to polypropylene, polyethylene, natural or syntheticrubber, T.P.E. Preferably the flexible substrate is a thermoformablepolymer which can be co-extruded with and may fully encapsulate thecarrier or the longitudinal and transverse members. Similarly, if thecarrier consists of a substantially flat metal strip it may be fully orpartially encapsulated in the flexible substrate.

If the longitudinal and transverse members are so fully encapsulatedthey may be protected from corrosion by the flexible substrate.

The opposite clamping members may further include gripping means adaptedto compressively engage the base of the barrier to hold same in the baseof the carrier. Preferably the gripping means consists of at least onefin on each clamping member which projects inwardly of the carrier andtowards its base, and which extends along the carrier. The fins form aclose fitting engagement with the base of the barrier and may grip thebarrier as a result of compressive force exerted by the clampingmembers. The gripping means may be formed integrally with the flexiblesubstrate. More than one fin may be provided on each clamping member.Other gripping means such as studs, fingers, ribs or the like may beused in addition to or in substitution of fins.

In one embodiment, one or more of the longitudinal members may be heatmeltable such that when the flexible substrate is co-extruded with thelongitudinal and transverse members, the heat meltable longitudinalmembers melt into and form part of the substrate.

The flexible substrate may further include a backing profile in anyselected shape. The backing profile may be integral with the flexiblesubstrate or it may be a separate element or elements connected to theflexible substrate. The backing profile may assist in joining orattaching the flexible barrier in its desired application. For example,the backing profile may be an elongate projection running along thelength of the barrier, for example, "T"-shaped in cross-section toenable the barrier to be fed along a corresponding channel in the objectto which the barrier is to be attached. A wide variety of backingprofiles may be utilized.

In another embodiment, the carrier may include a leg extending away fromthe U-shaped portion of the carrier and adapted to facilitate connectionof the barrier to an object. The leg may be a lateral extension of thecarrier and the transverse members may extend into the leg such that theleg may be formed into a desired shape suitable for affixing to anobject such as a truck wheel arch, door surround or the like. Dependingupon the properties required of the leg for connection with an object,the transverse member may extend part or all the way into the leg. Theleg may be formed into a desired shape or arrangement during the processwhereby the carrier is formed into the U-shaped profile. The leg may beaffixed to the desired object by any suitable means such as rivetting,hook and loop or Velcro (Registered Trade Mark) type fastners, or thelike, are as are known in the art. Alternatively, the leg may be formedinto a U-shaped clamping member which retentively grips the object towhich it is affixed in a similar manner which the carrier grips thebarrier member. For example, the leg may retentively grip a flange inthe wheel arch of a vehicle. In this embodiment similar considerationsof resistance to splay are relevant as discussed herein with referenceto Table A.

The flexible substrate may be of any suitable colour or texture. Thesubstrate may be of a particular colour to indicate the characteristicsof the barrier, such as the type of brush or barrier fin, the strengthor application of the barrier or the like.

The resilient barrier member may be any suitable barrier known in theart. The barrier may be an elongate resilient web or fin which extendsalong the axis of the carrier. Such a fin may be made from a resilientmaterial such as rubber or a web of polyethylene film or the like. Thefin may act as a wiper in the same manner as an automotive windscreenwiper, or even as a squeegee.

Preferably, the barrier member is in the form of a brush consisting of aplurality of bristles which extend substantially perpendicular to theaxis of the barrier. The bristles may be made from any suitable bristlematerial which is known in the brush making art. The bristles may bemade from, for example, nylon, carbon fibre, horse-hair, cotton,polypropylene, polyethylene or the like and may be in any length, shape,form, stiffness, colour or thickness. The brush may consist of a blendof two or more different types of bristle. The brush may consist of ablend of electrically conductive and non-conductive bristles. Theparticular application for which the barrier is intended will dictatethe type of bristle which should be utilised. The skilled addressee willreadily appreciate the suitability of a particular type of bristle for aspecific application.

In one embodiment, the flexible substrate encapsulating the carrier maybe melted into or otherwise additionally bonded to the barrier material.

According to another aspect of the invention there is provided a methodfor making an elongate barrier comprising:

(a) providing an elongate carrier which is flexible in all directionstransverse to its length and being deformable across its width into aselected shape, said carrier retaining said selected shape after suchdeformation;

(b) providing a resilient barrier member having a base portion and abody;

(c) positioning the base portion of said barrier member about saidcarrier; and

(d) deforming said carrier such that the carrier retentively grips thebase portion of said barrier member.

Preferably where the barrier member is a brush, a plurality of bristlesare positioned about said carrier and the carrier is then deformed togrip part of the bristles. The bristles may be positioned perpendicularto the axis of the carrier, and the carrier deformed into a "U" or "C"shape in transverse section having a base and opposite clamping memberswhich retentively grip that portion of the bristles which werepositioned about the carrier. The carrier may be partially preformedinto a "U" or "C" shape, but preferably it has a substantially flatupper surface which forms the base and clamping members once the carrieris deformed into the "U" or "C" shape. Surprisingly, conventionalelongate brush-making machinery may be utilized to form the elongatebarrier of the present invention. In such machinery, the bristles may beassembled in a magazine and passed onto the carrier member in a similarfashion to that used for conventional rigid backed elongate brushes.

The barrier may include a retaining member which is positioned on top ofthe base portion of the bristles before the carrier is deformed. In apreferred embodiment, the base portion of the bristles are compressedsecurely between the opposite clamping members of the carrier and theretaining member. The opposite clamping members of the carrier arecrimped around the retaining member so that the bristles are heldsecurely therebetween. The retaining member may be any suitable size orshape and preferably runs substantially along the length of the barrier.The retaining member may be a wire. The wire may be made from anysuitable metal such as stainless steel, mild steel, aluminium, copper orthe like. Preferably the wire is a low carbon steel wire. The wire maybe coated with any suitable material such as a polymeric material. Thisis advantageous if the retaining member needs to be protected fromcorrosion. Alternatively, the retaining member may be an extrudedpolymeric material of any desired shape. In order to facilitateflexibility of the barrier, the retaining member should also be flexiblealong the length of the barrier.

In another embodiment, there may be provided a secondary barrier memberwhich runs along the length of the barrier. Preferably, when the primarybarrier consists of a plurality of bristles, the secondary barrierconsists of an elongate flexible fin which runs parallel to the array ofbristles. The secondary barrier may consist of an elongate web which maybe incorporated into the barrier in the same manner as the bristles,i.e. by laying the secondary barrier along the length of the carrierbeneath the retaining member (where provided) and either on top of orbeneath the bristles. When the barrier is formed, the secondary barriermember may be folded about the retaining member and retained in the baseof the carrier in the same manner as the bristles. Alternatively, theretaining member may be provided with a portion extending perpendicularto the axis of the retaining member. The extending portion may be a ribor fin which runs along the length of the retaining member or it may bea plurality of bristle-like or short fin projections.

BRIEF DESCRIPTION OF THE DRAWINGS

It will now be convenient to describe the invention with reference tothe accompanying drawings. It is to be understood that the drawings andthe following description relate to a preferred embodiment only and arenot intended to limit the scope of the present invention.

FIG. 1 is a perspective view of a portion of an elongate barrier made inaccordance with the present invention.

FIG. 2 is a cut away plan view of a portion of an elongate carrier ofthe present invention.

FIG. 3 is a perspective view of a portion of an elongate barrier of thepresent invention before forming.

FIG. 4 is a perspective view of a portion of an elongate barrier made inaccordance with another embodiment of the present invention.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

Elongate barrier 1 includes an elongate carrier 3. Elongate carrier 3has an axis generally along the line shown 5,5'. The carrier 3 isflexible in all directions along the axis 5,5', both up and down asrepresented by arrows 7 and 9 and side to side represented as arrows 11and 13. Carrier 3 may also be twisted about axis 5,5'. The elongatecarrier 3 may be flexible substantially along the full length of theaxis 5,5' although portions of the carrier 3 may be rigid in one or moredirections along the axis 5,5'. Perpendicular to the axis 5,5' thecarrier 3 is capable of retaining a selected shape. In FIG. 1, theselected shape in transverse section is substantially a U-shaped profile15 although other shapes may equally be adopted such as a "C" profile.The selected shape must be such that resilient barrier member 17 isretentively gripped by the carrier 3 when the carrier 3 is deformed intothe selected shape.

Carrier 3 has a base portion 4 and opposite clamping members 6 and 8.Carrier 3 may include a backing profile member 19 which is adapted toenable barrier 1 to be easily attached in situ where the barrier isrequired.

In FIG. 4 carrier 3 includes a leg 10 which extends away from U-shapedprofile 15. Leg 10 may include a fastening means 12 such as Velcro(Registered Trade Mark) or the like to facilitate affixing to an object.

Carrier 3 may also include gripping means shown in FIG. 1 as lugs 21 onthe inside walls 23 of carrier 3. Lugs 21 may act to assist in clampingbarrier member 17 within the U-shaped profile 15. Any other suitablemeans may be provided on the inside walls 23 to assist in firmly holdingbarrier member 17. Such means may include ribs, studs, fins, or thelike. In FIG. 4, gripping means are inwardly projecting ribs 22 onclamping members 6 and 8.

Barrier member 17 has a base portion 25 and a body 27. In FIG. 1 barriermember 17 consists of a primary barrier member consisting of a pluralityof bristles 29 and a secondary barrier member consisting of an elongatefin 31. The base portion 25 of bristles 29 and fin 31 are located withinthe U-shaped profile 15. The body 27 of bristles 29 and fin 31 extendbeyond carrier 3.

In FIG. 4, barrier member 17 consists of a plurality of bristles 29.

Retaining member 33 is located within the U-shaped profile 15, and thebase portion 25 of bristles 29 and fin 31 are folded about retainingmember 33. The clamping action of the U-shaped profile around retainingmember 33 and against barrier member 17 holds the base portion 25 ofbarrier member 17 within carrier 3.

In FIG. 2, carrier 3 is shown to consist of a flexible substrate 35 inwhich there is embedded a continuous wire 37 formed into a sinuate shapewhich extends along the length of the carrier 3. A plurality of strands39 are knitted in co-operation with wire 37. Wire 37 provides transversemembers 41 which give carrier 3 the property of retaining the selectedshape after carrier 3 is deformed. In FIG. 4 the transverse members mayextend into leg 10 such that leg 10 may be formed into a desired shape.

FIG. 3 shows the arrangement of the carrier 3, barrier member 17 andretaining member 33 before carrier 3 is deformed. Retaining member 33 isshown as a wire 36 with a coating 38. Carrier 3 has an upper surface 19which, when carrier 3 is deformed, forms inside walls 23 as shown inFIG. 1. Bristles 29 may be laid over upper surface 19 such that the baseportion 25 of bristles 29 overlies upper surface 19. Retaining member 33may then be positioned over the base portion 25 of bristles 29. To formthe barrier, carrier 3, bristles 29 and retaining member 33 aresimultaneously passed through machinery which deforms clamping members 6and 8 around retaining member 33 and lugs 21 or ribs 22 abut againstbristles 29 such that the base portion 25 of the bristles are retainedby the carrier 3. This forming method can be done as a continuousprocedure. Conventional elongate brush making machinery may be utilizedwith minor modifications to account for the dimensions of the carrier.After formation of the elongate brush, the bristles may be cropped suchthat the bristles are all of equal length.

It is to be understood that various modifications, additions, and/oralterations may be made to the parts previously described withoutdeparting from the ambit of the present invention.

What is claimed is:
 1. An elongate barrier comprising an elongatecarrier which is flexible in all directions along its length and whichis capable of retaining in transverse section substantially a U-shape,said carrier including a longitudinal member, and a transverse memberextending transversely of said longitudinal member, said transversemember being deformable such that said carrier is deformed to saidU-shape in which said carrier has a base and opposite clamping members;andat least one resilient barrier member extending along the length ofsaid carrier having a base portion and a body portion, wherein thecarrier is deformable into said U-shape around the base portion of saidbarrier member and said clamping members retain the base portion of thebarrier member in the base of the carrier, such that when the carrier isflexed, the barrier member is retained in said carrier.
 2. An elongatebarrier according to claim 1, wherein said longitudinal member consistsof an elongate flexible strip and said transverse member consists of aplurality of fingers projecting laterally from said longitudinal member.3. An elongate barrier according to claim 1, wherein said transversemember consists of a continuous sinuate wire extending along the lengthof said carrier and zigzagging across the width of said carrier andwherein said longitudinal member consists of one or more strandsco-operating with said wire to retain said wire in said sinuate shape.4. An elongate barrier according to claim 1, wherein said carrierfurther includes a flexible substrate enveloping substantially all ofsaid base and said clamping members.
 5. An elongate barrier according toclaim 4, wherein said carrier further includes gripping means on saidclamping members for compressively engaging said barrier member to holdthe barrier member in the base of said carrier.
 6. An elongate barrieraccording to claim 5, wherein said gripping means is integral with saidflexible substrate.
 7. An elongate barrier according to claim 5, whereinsaid gripping means comprises a rib extending along the length of eachclamping member and projecting inwardly towards the opposite clampingmember.
 8. An elongate barrier according to claim 1, wherein saidcarrier further includes a connection member for connecting said barrierto a desired site.
 9. An elongate barrier according to claim 8, whereinsaid connection member comprises a leg projecting from said carrier toretentively engage the desired site.
 10. An elongate barrier accordingto claim 8, wherein said connection member includes one of a pair ofhook and loop fasteners, the other of the fasteners being attached tothe desired site.
 11. An elongate barrier according to claim 1, whereinsaid barrier member comprises a plurality of bristles collectivelyforming a base portion retained in said carrier.
 12. An elongate barrieraccording to claim 11, wherein the base portion of said bristles passesaround a retaining member disposed in the base of said carrier and saidretaining member is held in the base of said carrier by said clampingmembers.
 13. An elongate barrier according to claim 12, wherein saidretaining member comprises a flexible wire extending along the length ofsaid carrier.
 14. An elongate barrier according to claim 1, wherein thecarrier has a resistance to splaying which is greater than about 50Newtons.
 15. An elongate barrier according to claim 1, wherein thecarrier has a resistance to splaying which is greater than about 100Newtons.
 16. An elongate barrier comprising an elongate carrierincluding a substrate of flexible plastic material and longitudinal andtransverse members embedded in said substrate, said substrate of saidcarrier being flexible in all directions along its length and beingbendable to a U-shape which the carrier retains due to the longitudinaland transverse members embedded in said substrate, said carrier forming,when in said U-shape, a base and opposite legs extending from said baseconstituting clamping members, and at least one resilient barrier memberextending along the length of said carrier and transversely therebeyond,such that when the carrier is bent to said U-shape, said barrier memberis bent therewith and is retained by said clamping members of saidcarrier.
 17. An elongate barrier according to claim 16, wherein saidtransverse member forms a sinuate wire which is interknitted with saidlongitudinal member.
 18. An elongate barrier according to claim 16,further comprising a retaining wire extending along the length of saidcarrier and superimposed on said barrier member so that when the carrieris bent to U-shape said barrier member is bent around said retainingmember.
 19. An elongate barrier according to claim 16, comprising aconnecting member extending from said carrier and including means forattachment to an external site.